William Joseph Speirs is believed to have been born on 2 November 1895 at Irvinebank, Queensland, to parents John and Catharine nee Tracey. He mobilised for war service in August 1914 as part of the “Pacific Expedition” for 6 weeks. Speirs embarked at Cairns, Queensland for garrison duty on Thursday Island on 8 August 1914. Approximately a week later, on 14 August 1914, he enlisted for overseas war service. He re-embarked at Thursday Island aboard HMAS Kanowna on 16 August 1914 to participate in the capture of German New Guinea. He was formally recognised as joining the Australian Naval and Military Expeditionary Force on 6 September 1914. However, he did not participate in the capture of German New Guinea and returned to Townsville on 18 September 1914 as a result of trouble caused by firemen aboard the troopship. He was discharged on 18 September 1914.
He was working as a butcher, aged 20, when he enlisted in the Australian Imperial Force on 5 October 1914. His mother gave permission for him to volunteer on 26 September 1914. Speirs embarked at Melbourne with the 15th Battalion aboard HMAT Ceramic on 22 December 1914. He served at Gallipoli where he was promoted to Lance Corporal 8 May 1915 and again to Corporal on 17 July 1915. His service record shows that he was a bugler and he also became bandmaster of the 15th Battalion Band. At his own request, he returned to the rank of Private in 1916. On 23 September 1918, Speirs was granted leave to return to Australia and returned aboard Kaiser-i-Hind on 8 October 1918.